U.S. patent application number 12/053335 was filed with the patent office on 2009-06-04 for touch screen, touch panel and manufacturing method thereof.
This patent application is currently assigned to DELTA ELECTRONICS, INC.. Invention is credited to Chii-How Chang, Sean Chang, Yang-Lin Chen.
Application Number | 20090140990 12/053335 |
Document ID | / |
Family ID | 40675211 |
Filed Date | 2009-06-04 |
United States Patent
Application |
20090140990 |
Kind Code |
A1 |
Chang; Sean ; et
al. |
June 4, 2009 |
TOUCH SCREEN, TOUCH PANEL AND MANUFACTURING METHOD THEREOF
Abstract
A touch panel includes a substrate, a conductive circuit layer,
a resistive layer and a dielectric layer. The substrate has a touch
area and a peripheral area surrounding the touch area. The
conductive circuit layer is formed on the peripheral area of the
substrate. The resistive layer covers the conductive circuit layer
and the touch area of the substrate. The dielectric layer is formed
on the resistive layer. The conductive circuit layer includes a
plurality of signal terminals disposed on corner surfaces of the
substrate as the corner electrodes of the conductive circuit
layer.
Inventors: |
Chang; Sean; (Taoyuan Hsien,
TW) ; Chang; Chii-How; (Taoyuan Hsien, TW) ;
Chen; Yang-Lin; (Taoyuan Hsien, TW) |
Correspondence
Address: |
Muncy, Geissler, Olds & Lowe, PLLC
P.O. BOX 1364
FAIRFAX
VA
22038-1364
US
|
Assignee: |
DELTA ELECTRONICS, INC.
|
Family ID: |
40675211 |
Appl. No.: |
12/053335 |
Filed: |
March 21, 2008 |
Current U.S.
Class: |
345/173 |
Current CPC
Class: |
G06F 3/041 20130101;
G06F 2203/04113 20130101; G06F 3/0444 20190501 |
Class at
Publication: |
345/173 |
International
Class: |
G06F 3/041 20060101
G06F003/041 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 30, 2007 |
TW |
096145565 |
Claims
1. A touch panel comprising: a substrate having a touch area and a
peripheral area; a conductive circuit layer formed on the
peripheral area of the substrate; a resistive layer formed on the
conductive circuit layer and the touch area of the substrate; and a
dielectric layer formed on the resistive layer or a portion of the
resistive layer located on the touch area.
2. The touch panel according to claim 1, wherein the conductive
circuit layer comprises a plurality of signal terminals disposed on
corner surfaces of the substrate to serve as corner electrodes of
the conductive circuit layer.
3. The touch panel according to claim 1, wherein the substrate is a
glass substrate or a plastic substrate.
4. The touch panel according to claim 1, wherein a material of the
conductive circuit layer comprises copper or silver glue.
5. The touch panel according to claim 1, wherein the conductive
circuit layer comprises discontinuous electrodes.
6. The touch panel according to claim 1, wherein a material of the
resistive layer comprises a transparent conductive material.
7. The touch panel according to claim 6, wherein the transparent
conductive material comprises indium tin oxide (ITO), indium zinc
oxide (IZO), aluminum-doped zinc oxide (AZO), tin oxide
(SnO,SnO.sub.2), zinc gallium oxide or zinc oxide.
8. The touch panel according to claim 1, wherein the dielectric
layer at least comprises an anti-reflective layer and/or a
hardening layer.
9. The touch panel according to claim 8, wherein a material of the
anti-reflective layer comprises silicon oxide, silicon nitride or
silicon nitrogen oxide, niobium oxide, titanium oxide, aluminum
oxide, aluminum nitride, tantalum oxide, zirconium oxide, magnesium
oxide or Cryolite (Na.sub.3AlF.sub.6).
10. The touch panel according to claim 1, further comprising: a
protective layer formed on a portion of the dielectric layer on the
peripheral area or a portion of the resistive layer on the
peripheral area.
11. The touch panel according to claim 10, wherein a material of
the protective layer comprises epoxy, acrylic glue or silicon.
12. A touch screen comprising: a touch panel comprising: a
substrate having a touch area and a peripheral area, a conductive
circuit layer formed on the peripheral area of the substrate, a
resistive layer formed on the conductive circuit layer and the
touch area of the substrate, and a dielectric layer formed on the
resistive layer or a portion of the resistive layer located on the
touch area; and an external circuit for applying voltage to the
touch panel and receiving current from the touch panel.
13. The touch screen according to claim 12, wherein the dielectric
layer at least comprises an anti-reflective layer and/or a
hardening layer.
14. The touch screen according to claim 13, wherein a material of
the anti-reflective layer comprises silicon oxide, silicon nitride
or silicon nitrogen oxide, niobium oxide, titanium oxide, aluminum
oxide, aluminum nitride, tantalum oxide, zirconium oxide, magnesium
oxide or cryolite (Na.sub.3AlF.sub.6).
15. A manufacturing method of a touch screen comprising steps of:
providing a substrate having a touch area and a peripheral area;
forming a conductive circuit layer on the peripheral area of the
substrate; forming a resistive layer on the conductive circuit
layer and the touch area of the substrate; and forming a dielectric
layer on the resistive layer or a portion of the resistive layer
located on the touch area.
16. The method according to claim 15, wherein the conductive
circuit layer comprises discontinuous electrodes and a plurality of
signal terminals disposed on corner surfaces of the substrate to
serve as corner electrodes of the conductive circuit layer.
17. The method according to claim 15, wherein the conductive
circuit layer is formed on the substrate by coating, printing,
adhering or deposition.
18. The method according to claim 15, wherein the dielectric layer
at least comprises an anti-reflective layer and/or a hardening
layer, and a material of the anti-reflective layer comprises
silicon oxide, silicon nitride, silicon nitrogen oxide, niobium
oxide, titanium oxide, aluminum oxide, aluminum nitride, tantalum
oxide, zirconium oxide, magnesium oxide or cryolite
(Na.sub.3AlF.sub.6).
19. The method according to claim 15, further comprising a step of:
forming a protective layer on a portion of the dielectric layer
located on the peripheral area or a portion of the resistive layer
located on the peripheral area, wherein a material of the
protective layer comprises epoxy, acrylic glue or silicon.
20. The method according to claim 15, wherein the steps of forming
the resistive layer and the dielectric layer are performed by one
deposition apparatus.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This Non-provisional application claims priority under 35
U.S.C. .sctn.119(a) on Patent Application No(s). 096145565 filed in
Taiwan, Republic of China on Nov. 30, 2007, the entire contents of
which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of Invention
[0003] The invention relates to a touch screen, a touch panel and a
manufacturing method thereof. More particularly, the invention
relates to a touch panel and a touch screen having a resistive
layer and an anti-reflective layer formed on the resistive
layer.
[0004] 2. Related Art
[0005] Recently, the touch panel has been widely applied to many
kinds of electronic products, such as the mobile communication
device, digital camera, MP3 player, PDA, GPS hand-held PC or ultra
mobile PC (UMPC). In the above-mentioned applications, the touch
panel is associated with a display screen to form a touch screen.
Regarding to the touch screen, the sensitivity and preciseness
thereof are very importance factors for the product performance. In
addition, the manufacturing processes of the touch panel will
affect the production cost thereof.
[0006] FIG. 1 shows a conventional touch screen 1, and FIG. 2 is a
sectional view showing a part of the touch screen 1. The touch
screen includes a touch panel 11 and an external circuit 12. The
touch panel 11 includes a substrate 111, a resistive layer 112, a
conductive circuit layer 113, a plurality of signal terminals 114
and a protective layer 116. The substrate 111 has a touch area
T.sub.1 and a peripheral area P.sub.1 disposed around the touch
area T.sub.1. The conductive circuit layer 113 and the signal
terminals 114 are formed on a portion of the resistive layer 112
located on the peripheral area P.sub.1. The protective layer 116
covers the conductive circuit layer 113 and the signal terminals
114 for protection. The external circuit 12 is electrically
connected to the signal terminals 114.
[0007] The operation principle of the touch screen 1 will be
described hereinafter. When the signal terminals 114 are charged,
the entire resistive layer 112 has an electric field with the
distribution of the equipotential lines L.sub.1 as is shown in FIG.
3. If a user presses a position of the resistive layer 112, the
electric field of the resistive layer 112 changes and the signal
terminals 114 located at the corner surfaces will generate signals
according to the current variations. Then, the generated signals
are transmitted to the backend through the external circuit 12, so
that the pressed position can be obtained after the further process
of signals received by the backend.
[0008] However, as shown in FIG. 2, the conductive circuit layer
113 is in contact with the resistive layer 112 by only the bottom
surface A.sub.1. Thus, the current transmitted from the conductive
circuit layer 113 to the resistive layer 112 is constricted, so
that the potential of the electric field generated by the resistive
layer 112 is decreased, thereby affecting the sensitivity of the
touch screen 1. In addition, the end portions E.sub.1 of the
equipotential lines L.sub.1 as shown in FIG. 3 are seriously
crooked, which decreases the preciseness of the touch screen 1.
SUMMARY OF THE INVENTION
[0009] In view of the foregoing, the invention is to provide a
touch panel and touch screen that have high sensitivity and
preciseness, simplified manufacturing processes, enhanced
performance and decreased manufacturing cost.
[0010] To achieve the above, the invention discloses a touch panel
including a substrate, a conductive circuit layer, a resistive
layer and a dielectric layer. The substrate has a touch area and a
peripheral area. The conductive circuit layer is formed on the
peripheral area of the substrate. The resistive layer covers the
conductive circuit layer and the touch area of the substrate. The
dielectric layer is formed on the resistive layer. Herein, the
conductive circuit layer includes a plurality of signal terminals
disposed on corner surfaces of the substrate to serve as corner
electrodes of the conductive circuit layer. The signal terminals
are used to apply voltage to the touch panel and receive
current.
[0011] In addition, the invention also discloses a touch screen
including a touch panel and an external circuit. The touch panel
includes a substrate, a conductive circuit layer, a resistive layer
and a dielectric layer. The substrate has a touch area and a
peripheral area. The conductive circuit layer is formed on the
peripheral area of the substrate. The resistive layer covers the
conductive circuit layer and the touch area of the substrate. The
dielectric layer is formed on the resistive layer. The conductive
circuit layer includes a plurality of signal terminals disposed on
corner surfaces of the substrate to serve as corner electrodes of
the conductive circuit layer. The signal terminals are electrically
connected to the external circuit so as to apply voltage to the
touch panel and receive current from touch panel.
[0012] As mentioned above, in the touch panel and touch screen of
the present invention, the conductive circuit layer is formed on
the substrate, and the resistive layer is formed on the conductive
circuit layer. Thus, more surfaces of the conductive circuit layer
can be in contact with the resistive layer so as to increase the
transmitted current and enhance the sensitivity and preciseness. In
addition, since the dielectric layer is formed on the resistive
layer, the resistive layer and the dielectric layer can be
performed in a single deposition apparatus. Therefore, the
manufacturing processes can be simplified, the performance can be
enhanced and the manufacturing cost can be decreased.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The present invention will become more fully understood from
the subsequent detailed description and accompanying drawings,
which are given by way of illustration only, and thus are not
limitative of the present invention, and wherein:
[0014] FIG. 1 is a schematic illustration showing a conventional
touch screen;
[0015] FIG. 2 is a sectional view showing a part of the
conventional touch screen;
[0016] FIG. 3 is a schematic illustration showing the distribution
of the equipotential lines in the electric field of the touch
screen;
[0017] FIG. 4 is a schematic illustration showing a touch screen
according to a preferred embodiment of the present invention;
[0018] FIG. 5 is a sectional view showing a part of the touch
screen of FIG. 4;
[0019] FIG. 6 is a sectional view showing a part of another touch
screen according to the embodiment of the present invention;
and
[0020] FIG. 7 is a schematic illustration showing the distribution
of the equipotential lines in the electric field of the touch
screen of FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION
[0021] The present invention will be apparent from the following
detailed description, which proceeds with reference to the
accompanying drawings, wherein the same references relate to the
same elements.
[0022] FIG. 4 shows a touch screen 2 according to a preferred
embodiment of the present invention, and FIG. 5 is a sectional view
showing a part of the touch screen 2. With reference to FIGS. 4 and
5, the touch screen 2 includes a touch panel 21 and an external
circuit 22. The touch panel 21 includes a substrate 211, a
conductive circuit layer 213, a resistive layer 212, a dielectric
layer 215 and a protective layer 216.
[0023] The substrate 211 has a touch area T.sub.2 and a peripheral
area P.sub.2 disposed around the touch area T.sub.2. In the
embodiment, the substrate 221 can be, for example but not limited
to, a glass substrate or a plastic substrate. The conductive
circuit layer 213 is formed on the peripheral area P.sub.2 of the
substrate 211 by coating, printing, adhering or deposition. The
conductive circuit layer 213 can be discontinuous electrodes as the
dot lines shown in FIG. 4. The material of the conductive circuit
layer 213 is, for example, copper or silver glue.
[0024] The conductive circuit layer 213 includes a plurality of
signal terminals 214 disposed on the corner surfaces of the
substrate 211. In the embodiment, the signal terminals 214 can
serve as the corner electrodes of the conductive circuit layer 213
for applying voltage to and receiving current from the touch panel
2. The signal terminals 214 and the conductive circuit layer 213
can be formed simultaneously. The external circuit 22 is
electrically connected to the signal terminals 214.
[0025] The resistive layer 212 covers the conductive circuit layer
213 and the touch area T.sub.2 of the substrate 21. The material of
the resistive layer 212 can be transparent conductive metal oxide
such as indium tin oxide (ITO), indium zinc oxide (IZO),
aluminum-doped zinc oxide (AZO), tin oxide (SnO,SnO.sub.2), gallium
zinc oxide (GZO) or zinc oxide (ZnO).
[0026] The dielectric layer 215 is formed on the resistive layer
212. In the embodiment, the dielectric layer 215 includes at least
a hardening layer and/or an anti-reflective layer. In practice, the
hardening layer can be formed before or after the formation of the
anti-reflective layer. The material of the anti-reflective layer
can include, for example, silicon oxide (SiO), silicon nitride
(SiN), silicon nitrogen oxide (SiON), niobium oxide, titanium
oxide, aluminum oxide, aluminum nitride, tantalum oxide, zirconium
oxide, magnesium oxide or cryolite (Na.sub.3AlF.sub.6). To be
noted, the resistive layer 212 and the dielectric layer 215 can be
formed by the same deposition apparatus, so that the manufacturing
processes can be simplified.
[0027] Alternatively, the dielectric layer can have another aspect
as shown in FIG. 6. Referring to FIG. 6, a touch screen 2' includes
a dielectric layer 215' disposed on a portion of the resistive
layer 212 located on the touch area T.sub.2.
[0028] The protective layer 216 is formed on a portion of the
dielectric layer 215 located on the peripheral area P.sub.2, as
shown in FIG. 5, or a portion of the resistive layer 212 located on
the peripheral area P.sub.2, as shown in FIG. 6. The material of
the protective layer 216 can be, for example, epoxy, acrylic glue
or silicon. In the embodiment, the protective layer 216 can protect
the conductive circuit layer 213 and the signal terminals 214.
[0029] When the signal terminals 214 are charged, the entire
resistive layer 212 has an electric field with the distribution of
the equipotential lines L.sub.2 shown in FIG. 7. If a user presses
a position of the touch area T.sub.2, the electric field of the
resistive layer 212 changes and the signal terminals 214 located at
the corner surfaces will receive the varied signals. Then, the
generated signals are transmitted to the backend through the
external circuit 22, so that the pressed position can be obtained
after the further process of signals received by the backend. The
external circuit 22 includes, for example, the trace(s), flat
cable(s) and chip(s).
[0030] Referring to FIG. 5, the conductive circuit layer 213 is in
contact with the resistive layer 212 by not only the bottom surface
A.sub.21 but also the side surfaces A.sub.22 and A.sub.23. Compared
with the prior art, the present invention can increase the
transmitted current as well as the potential of the electric field
formed by the conductive circuit layer 213. In addition, the end
portions of the equipotential lines L.sub.2 as shown in FIG. 7 are
not crooked (compared with the end portions E.sub.1 as shown in
FIG. 3), so that the preciseness of the touch screen 2 can be
enhanced.
[0031] In summary, in the touch panel and touch screen of the
present invention, the conductive circuit layer is formed on the
substrate, and the resistive layer is formed on the conductive
circuit layer. Thus, more surfaces of the conductive circuit layer
can be in contact with the resistive layer so as to increase the
transmitted current and enhance the sensitivity and preciseness. In
addition, since the dielectric layer is formed on the resistive
layer, the resistive layer and the dielectric layer can be
performed in a single deposition apparatus. Therefore, the
manufacturing processes can be simplified, the performance can be
enhanced and the manufacturing cost can be decreased.
[0032] Although the present invention has been described with
reference to specific embodiments, this description is not meant to
be construed in a limiting sense. Various modifications of the
disclosed embodiments, as well as alternative embodiments, will be
apparent to persons skilled in the art. It is, therefore,
contemplated that the appended claims will cover all modifications
that fall within the true scope of the present invention.
* * * * *